Addressed PR comments and re-organized code structure.

scripts/tests/run_tv_casting_test.py

@@ -21,6 +21,16 @@
 
 import click
 
+LINUX_TV_APP_LOGS = './scripts/tests/Linux-tv-app-logs.txt'
+LINUX_TV_CASTING_APP_LOGS = './scripts/tests/Linux-tv-casting-app-logs.txt'
+
+RUN_INTERVAL = 5
+PARSE_INTERVAL = 15
+
+VENDOR_ID = 65521
+PRODUCT_ID = 32769
+DEVICE_TYPE = 35
+
 
 # Dump the logs to the console in the case of an error.
 def dump_logs_to_console(log_file):
@@ -37,10 +47,46 @@ def remove_log_file(log_file):
         print("The file does not exist.")
 
 
+# Whenever a failure is discovered, we should print 'Discovery failed!',
+# dump the logs, clean up the log files, exit on error.
+def handle_discovery_failure():
+    print('Discovery failed!')
+
+    dump_logs_to_console(LINUX_TV_CASTING_APP_LOGS)
+
+    remove_log_file(LINUX_TV_CASTING_APP_LOGS)
+    remove_log_file(LINUX_TV_APP_LOGS)
+
+    sys.exit(1)
+
+
+# Helper function to extract the integer value from a string.
+def extract_value_from_string(line):
+    value = line.split(":")[-1].strip().replace('\x1b[0m', '')
+    value = int(value)
+
+    return value
+
+
+# Check if the discovered value matches the expected value.
+def check_expected_value(line, expected_value, value_name):
+    # Extract the integer value from the string
+    value = extract_value_from_string(line)
+
+    # If the discovered value does not match the expected value,
+    # print the error and handle the discovery failure.
+    if value != expected_value:
+        print(f'{value_name} does not match the expected value!')
+        print(f'Discovered {value_name}: {value}')
+        print(f'Expected {value_name}: {expected_value}')
+
+        handle_discovery_failure()
+
+
 # Read the logs from the Linux-tv-casting-app-logs.txt file.
 # The discovered commissioner(s) will be stored in a list along with their
 # vendor ID, product ID, and device type.
-def read_linux_tv_casting_app_logs(log_file):
+def parse_linux_tv_casting_app_logs(log_file):
 
     with open(log_file, 'r') as file:
         lines = file.readlines()
@@ -57,24 +103,11 @@ def read_linux_tv_casting_app_logs(log_file):
             print(line)
             print('Discovery success!')
 
-            remove_log_file('./scripts/tests/Linux-tv-casting-app-logs.txt')
-            remove_log_file('./scripts/tests/Linux-tv-app-logs.txt')
+            remove_log_file(LINUX_TV_CASTING_APP_LOGS)
+            remove_log_file(LINUX_TV_APP_LOGS)
 
             break
 
-        # If no commissioner was discovered, then something went wrong.
-        # Exit on error.
-        if "No commissioner discovered" in line:
-            print(line)
-            print('Discovery failed!')
-
-            dump_logs_to_console('./scripts/tests/Linux-tv-casting-app-logs.txt')
-
-            remove_log_file('./scripts/tests/Linux-tv-casting-app-logs.txt')
-            remove_log_file('./scripts/tests/Linux-tv-app-logs.txt')
-
-            sys.exit(1)
-
         # Look for "Discovered Commissioner"
         if "Discovered Commissioner" in line:
             print(line)
@@ -93,21 +126,15 @@ def read_linux_tv_casting_app_logs(log_file):
 
                 if "Vendor ID:" in next_line:
                     print(next_line)
-
-                    vendor_id = next_line.split(":")[-1].strip()
-                    vendor_id = vendor_id.replace('\x1b[0m', '')
+                    vendor_id = extract_value_from_string(next_line)
 
                 elif "Product ID:" in next_line:
                     print(next_line)
-
-                    product_id = next_line.split(":")[-1].strip()
-                    product_id = product_id.replace('\x1b[0m', '')
+                    product_id = extract_value_from_string(next_line)
 
                 elif "Device Type:" in next_line:
                     print(next_line)
-
-                    device_type = next_line.split(":")[-1].strip()
-                    device_type = device_type.replace('\x1b[0m', '')
+                    device_type = extract_value_from_string(next_line)
 
                 elif "commissioner(s) discovered" in next_line:
                     break
@@ -127,14 +154,8 @@ def read_linux_tv_casting_app_logs(log_file):
     # If the list of discovered commissioners is empty and we didn't find the "No commissioner discovered" string,
     # then something went wrong. Exit on error.
     if len(discovered_commissioners) == 0:
-        print('Discovery failed! No commissioner(s) discovered! The list of discovered commissioner(s) is empty!')
-
-        dump_logs_to_console('./scripts/tests/Linux-tv-casting-app-logs.txt')
-
-        remove_log_file('./scripts/tests/Linux-tv-casting-app-logs.txt')
-        remove_log_file('./scripts/tests/Linux-tv-app-logs.txt')
-
-        sys.exit(1)
+        print('No commissioner(s) discovered! The list of discovered commissioner(s) is empty!')
+        handle_discovery_failure()
 
 
 # Test if the Linux tv-casting-app is able to discover the Linux tv-app.
@@ -143,24 +164,48 @@ def read_linux_tv_casting_app_logs(log_file):
 # The log file of the tv-casting-app will be parsed for strings of interest
 # which will be printed to the console.
 def test_discovery_fn():
-    with open('./scripts/tests/Linux-tv-app-logs.txt', 'w') as fd1, open('./scripts/tests/Linux-tv-casting-app-logs.txt', 'w') as fd2:
+
+    with open(LINUX_TV_APP_LOGS, 'w') as fd1, open(LINUX_TV_CASTING_APP_LOGS, 'w') as fd2:
 
         # Run the Linux tv-app and write the output to file
         tv_app_rel_path = 'out/tv-app/chip-tv-app'
         tv_app_abs_path = os.path.abspath(tv_app_rel_path)
         subprocess.Popen(tv_app_abs_path, stdout=fd1, stderr=subprocess.PIPE, text=True)
 
-        time.sleep(5)
+        time.sleep(RUN_INTERVAL)
 
         # Run the Linux tv-casting-app and write the output to file
         tv_casting_app_rel_path = 'out/tv-casting-app/chip-tv-casting-app'
         tv_casting_app_abs_path = os.path.abspath(tv_casting_app_rel_path)
-        subprocess.Popen(tv_casting_app_abs_path, stdout=fd2, stderr=subprocess.PIPE, text=True)
+        tv_casting_app_process = subprocess.Popen(
+            tv_casting_app_abs_path, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
+
+        for line in tv_casting_app_process.stdout:
+            # Write the line to the Linux tv-casting-app log file
+            fd2.write(line)
+
+            # Fail fast if "No commissioner discovered" string found
+            if "No commissioner discovered" in line:
+                print(line)
+                handle_discovery_failure()
+
+            # Check if the Vendor ID, Product ID, and Device Type match the expected values
+            if "Vendor ID:" in line:
+                check_expected_value(line, VENDOR_ID, "Vendor ID")
+
+            elif "Product ID:" in line:
+                check_expected_value(line, PRODUCT_ID, "Product ID")
+
+            elif "Device Type:" in line:
+                check_expected_value(line, DEVICE_TYPE, "Device Type")
+
+            if "commissioner(s) discovered" in line:
+                break
 
     # Wait for the processes to finish writing before attempting to read
-    time.sleep(15)
+    time.sleep(PARSE_INTERVAL)
 
-    read_linux_tv_casting_app_logs('./scripts/tests/Linux-tv-casting-app-logs.txt')
+    parse_linux_tv_casting_app_logs(LINUX_TV_CASTING_APP_LOGS)
 
 
 @click.group()
@@ -174,5 +219,7 @@ def test_discovery():
 
 
 if __name__ == '__main__':
+    # Start with a clean slate by removing any previously cached entries.
+    os.system('rm -f /tmp/chip_*')
 
     main()